Thanks for the advice; I will try mineral oil and I think I can get by with
slowing the flow rate also.

Dan

"George Pontis" wrote in message
t...
In article , says...
I have recently installed a CO2 system in my 75 gallon aquarium and it is
working fine except for one little problem. I have a constant pH reading
of
7.1 thanks to the addition of CO2. Before CO2 my pH was 8.4. Very hard
water.

The problem is that when I fill my bubble counter half full of water, I
lose
it all within a week. I believe the bubble flow rate is too fast and the
large flow is causing the water to dissipate into the CO2 air tubing. I
replace it and then is starts over again.


In a chemistry lab a bubble counter would most likely be filled with
mineral oil.
Alternatively, some aquarium vendors offer a fluid for filling bubble
counters.
One of these two options should solve your problem so long as the flow
rate is
reasonable.